The invention generally relates to systems for transferring fluids from individual source containers to a receiving container, and more specifically relates to systems for transferring liquid drugs from individual vials, bottles, or bags to a single solution bag or bottle for administration to a patient.
In hospitals, it is frequently necessary to provide solutions for intravenous administration to a patient which contain a variety of drugs in a single solution container. A common example of such a need arises when a patient is receiving all of his nutritional needs intravenously. In this situation, the patient will typically receive a basic solution containing amino acids, dextrose, and fat emulsions which provide a major portion of the patient's nutritional needs. However, this solution is insufficient to maintain a patient for an extended period of time. Therefore, a typical total parenteral solution includes as many as eight to twelve additional additives. The additives are typically minute quantities of vitamins, minerals, electrolytes, etc. Therefore, when a pharmacist is preparing a solution for total parenteral nutrition, it is necessary for the pharmacist to individually add each of the additional additives to a solution container after the base solutions have been added. This is typically done with individual syringes and requires a relatively long time on the part of a pharmacist to accurately add each of the required additives.
An automatic compounding device has been recently developed to assist the pharmacist in preparing solutions for total parenteral nutrition. This device is described in U.S. Pat. Nos. 4,467,844 and 4,513,796 which are incorporated herein by reference. This device is used to assist the pharmacist in automatically compounding the base solution of amino acids, dextrose and fat emulsions. This system typically uses three or more peristaltic pumps to individually pump each of the base solutions from three or more separate source containers. Computer software also has been developed and is currently being used to program in the amount of solution required for a series of individual patients. This program is designed to operate the automated compounding equipment described in each of the above patents. This program is more fully described in U.S. patent application No. 665,268 filed Oct. 26, 1984, now U.S. Pat. No. 4,653,010, which is also incorporated herein in by reference. While this system has provided a tremendous advantage to the pharmacist, it is not useful for adding minute quantities of fluid additives to the receiving container. Therefore, a need exists for a device which can very accurately dispense very small quantities of fluids into a receiving container.